Luminescent mechanism of Y2SiO5:Ce phosphor powder

A luminescent mechanism was constructed for the broad band emission spectra of the X1 phase of the Y2SiO5:Ce phosphor powder. Four Gaussian peaks fit to the cathodoluminescent (CL) and photoluminescent (PL) spectra were attributed to the two different sites (A1 and A2) of the Ce3+ ion in the host matrix and the difference in orientation of the neighbour ions in the complex crystal structure. Each Ce3+ site gives rise to transitions from the 5d to the two (therefore two peaks) 4f energy levels (2F5/2 and 2F7/2 due to crystal field splitting). Energy transfer from other defect levels in the matrix was also observed.